These bonuses would stack also. So if you happen to get 3 Assassin units (because the 2 random units that were picked were both Assassins) then if they were all killed you would get +15% critical strike to the remaining units.
- Assassin death: +5% critical strike
- Knight death: +5% physical armor
- Wizard death: +5% damage
- Paladin death: +??
Haven't thought of a Paladin bonuses yet. If you have ideas I'm interested. Don't worry about what stats there are in the game just what would you think a Paladin bonus on death would look like.